I just bought a 2007 Malibu Wakesetter 23lsv (sweet boat, the family is so excited) and I am trying to figure out what kind of gas to put in it. The owner's manuel says 89 octane and recomends "Top Tier Fuel". That is all good but my question is ethanol or no ethanol? I hear a lot of bad things about puttng gas with 10% ethanol in your boat but from what I can tell Top Tier fuel has 10% ethanol in it. Sorry if I have repeated a thread but this is my new baby and I want to make sure I'm treating her right! Can anyone give me some advice on what gas to put in?

I stay away from Ethanol, I put it in a harley on accident... Man I didnt think I would ever get that thing to quit knocking... So from then on I always Look @ the signs... I dont know about your boat just wanted to put in my 2 cents

107 Seriously!!! I wouldn't know where to buy the gas. 91 is what most of the gas stations have here, every once in a while I can find 92. From what I can tell the octance boost additives have their own pros and cons.

K Money - Do you have any problems with the 10% ethanol that you put in your boat?

Just run whatever 89 rated fuel you can. It's better if it has 5% Ethanol or less. If you are at very high altitude you could run 87 rated fuel. You can always mix 87 and 91 rated fuel at 50% each and you've got 89 if you want.

107 fuel would hurt your gas mileage and reduce your horsepower output. I'll gladly take a bet that no one on the pro tour has even thought about running it.

On a side note, how can you tell if the gas has EtOH in it? What we see here is, "May contain up to 10% Ethanol", and I guess you could assume it has ethanol in it, but how would you know for sure? Are certain brands more or less likely? With the exception of a few Sinclair stations, I think every gas station has that same sticker on their pumps in AR.

Matt. The engine in your Supra is fuel injected and the ECU will advance or retard timing as needed so the engine does not knock. If you had knocking, get that thing looked at. No modern engine should ever knock. I can't even think how that could heppen. I can get it to happen in a turbo charged car if I add too much boost and run too lean. I can't figure out how that could happen from ethanol.

Back to the topic at hand. We habe only 10% ethanol here in IL and WI and my last boat ran for 10 years on it and never had a single issue.

Matt. The engine in your Supra is fuel injected and the ECU will advance or retard timing as needed so the engine does not knock

Exactly, Oregon has had 10% ethanol for several years, my carborated boat as well as every other vehicle (including 73 Challenger) has run fine. The high octane fuel requirement is a conspiracy as far as I'm concerned.

Matt. The engine in your Supra is fuel injected and the ECU will advance or retard timing as needed so the engine does not knock. If you had knocking, get that thing looked at. No modern engine should ever knock. I can't even think how that could heppen. I can get it to happen in a turbo charged car if I add too much boost and run too lean. I can't figure out how that could happen from ethanol.

Back to the topic at hand. We habe only 10% ethanol here in IL and WI and my last boat ran for 10 years on it and never had a single issue.

Tre, I had a knock from 10% ethenol in a Harley Davidson... I have never tryed it in a Boat..

Use the minimum recomended octane. That is what the engine is designed to run on. It all has to do with compression ratio, head design, and timing. If it calls for 89 octane minimum, run that. If you're running anything below the recommended octane rating, a modern engine can normally deal with that, but you're losing power because the engine is retarding the timing.

Hate N Pain "it's what I do for a living"?? Not in the gasoline business. The responses have been very helpful though. From what I am hearing the answer is buy gas that is at least 89 octane (because that's what the owner's manuel says), buy from a quality retailer and don't worry about the 10% ethanol. Thanks everyone for all your help.